> ## Documentation Index
> Fetch the complete documentation index at: https://developers.circle.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Transfer USDC on testnet between Aptos and Base using CCTP V1

> Explore this tutorial for transferring USDC between Aptos testnet and Base Sepolia Testnet via CCTP V1

<Warning>
  **This is CCTP V1 version. For the latest version, see [CCTP](/cctp)**.
</Warning>

To get started with CCTP V1 on Aptos testnet, follow the example scripts
provided
[on GitHub](https://github.com/circlefin/aptos-cctp/tree/master/typescript/example).
The examples use the
[Aptos SDK](https://www.npmjs.com/package/@aptos-labs/ts-sdk), to transfer USDC
to and from an address on Aptos testnet and an address on an external
blockchain.

<Warning>
  **Do not reuse keys** As a security measure, these scripts should only be used
  on a testnet for testing purposes. It is not recommended to reuse private keys
  across mainnet and testnet.
</Warning>

Summary of calling `deposit_for_burn()` (full runnable script can be found in
the aptos-cctp repository):

```ts theme={null}
// Aptos Testnet Stablecoin object
const BURN_TOKEN =
  "0x69091fbab5f7d635ee7ac5098cf0c1efbe31d68fec0f2cd565e8d168daf52832";

const aptosClient = new Aptos(new AptosConfig({ network: Network.TESTNET }));
const userAccount = Account.fromPrivateKey({
  privateKey: new Ed25519PrivateKey(APTOS_PRIVATE_KEY),
});

// Create a transaction with deposit for burn script
const buffer = readFileSync(
  "typescript/example/precompiled-move-scripts/testnet/deposit_for_burn.mv",
);
const bytecode = Uint8Array.from(buffer);
const amount = new U64(1);
const destinationDomain = new U32(6);
const burnToken = AccountAddress.from(BURN_TOKEN);
const mintRecipient = AccountAddress.from(evmSigner.address);
const functionArguments: Array<any> = [
  amount,
  destinationDomain,
  mintRecipient,
  burnToken,
];
const transaction = await aptosClient.transaction.build.simple({
  sender: userAccount.accountAddress,
  data: {
    bytecode,
    functionArguments,
  },
});
const pendingTxn = await aptosClient.signAndSubmitTransaction({
  signer: userAccount,
  transaction,
});
const depositForBurnTx = await aptosClient.waitForTransaction({
  transactionHash: pendingTxn.hash,
});
console.log(
  `Deposit for burn transaction completed successfully: https://explorer.aptoslabs.com/txn/${depositForBurnTx.hash}`,
);

// Fetch the event data from the transaction
const messageSentEvent = (
  depositForBurnTx as UserTransactionResponse
).events.find(
  (e: any) =>
    e.type ===
    `${MESSAGE_TRANSMITTER_PACKAGE_ID}::message_transmitter::MessageSent`,
);
```

Summary of calling `receive_message()` (full runnable script can be found in the
aptos-cctp repository):

```ts theme={null}
const bytecode = Uint8Array.from(
  fs.readFileSync(
    "typescript/example/precompiled-move-scripts/testnet/handle_receive_message.mv",
  ),
);
const functionArguments: Array<any> = [
  MoveVector.U8(messageBytes as Buffer),
  MoveVector.U8(attestationSignature),
];
const transaction = await aptosClient.transaction.build.simple({
  sender: userAccount.accountAddress,
  data: {
    bytecode,
    functionArguments,
  },
});
const pendingTxn = await aptosClient.signAndSubmitTransaction({
  signer: userAccount,
  transaction,
});
const receiveMessageTx = await aptosClient.waitForTransaction({
  transactionHash: pendingTxn.hash,
});
console.log(
  `Receive message transaction completed successfully: https://explorer.aptoslabs.com/txn/${receiveMessageTx.hash}`,
);
```